PurpleKrawler

whats the largest tire i can go with 3.55 gears? and it actually be okay? would i be able to go 33s?

FloydXJ

I also have a purple 99...we should be friends. Ha!

I am running 3.50 and 35s, and a manual. You can run just about anything you want on them, and it won't make a difference in the life of the drivetrain - it is mostly about trail and street comfort for your preferences. Even the effect on gas mileage is not very significant.

When I was on 33s and now on 35s with this gearing, I am getting 14/18 ish.

FloydXJ

BTW, with the auto the MPG might be a bit lower. The guys I have known on an auto with 33s/35s and 3.55s got around fine, but LOVED life when they switched to 4.88s.

PurpleKrawler

hmm ill keep that in mind, so id be okay to go 33s or 35s?

pickles

Im running 32's right now with 3.55 and AW4. I would go 33's max on these stock gears. But even 32" seems a bit much tire at times.

SLNPARTS1

i'm runing 33's with 307's with a manual i'm going to 355's..... does it lug real bad under stress say steep grades at road speed? do you find yourself changing gears/downshifting alot?

DKDunn04

I ran 33s with 3.55s for about a year, and I hated it. All the trails I did were in the mountains of Colorado, and on some of the steep runs I barley had enough power to get to the top in low range. I also drove over an 8500 ft pass to get to work every day, and I lost a lot of speed driving up it.

Skunkape

I got 33s and 3.55s and it does just fine,never been an issue but my engine is in really good condition and pretty strong.I have buddys with manual trannys running 35s with 3.55s and they seem to do fine off road Hwy is another story though.

caged

i've been running bias ply 36s with stock 3.55's for about 5 years now. but it's not my dd, however, i don't have any daily driving problems. but i'm also on relatively flat ground. we have some long hills, but no mountains.

lots of steep climbs off road with tones of rock and it climbs like a scared rabbit.
i'm sure i will like it when i go to 5.13 and a doubler, but for now, it works.
drives fine down the highway at 100kph.

PurpleKrawler

that makes me happy to hear, i really wanna go 33's or 35's

SLNPARTS1

i bought my xj with 35's with 307's boy it was weak but had a bad engine also... i installed a newer powerplant with some engine upgrades and have a manuial tranny also ... i down sized tires to 33's but going to install 355's all i'm going to do in hunt out of it and drive around i live in alabama no mountains here but we have a few steep hills but nothing extreme i will use it as a dd but not long commutes i think it will be fine what do you all think?

FloydXJ

In 5th gear, it will maintain on flat roads, but most grades, even minor ones will slow it down. I am in 4th most the time going up hills. On steeper 5%-7% grades that go for a while, it's in 3rd. If you are gearing down anyway, I would probably go lower than 3.55. Running at higher RPM's won't do much for your MPG in either direction, but you'll be happier with the road manners, I think. If it is ever convenient, I will probably do 4.56.

neeland

I'm running 36 bias ply tsl on 3.55s and a aw4 on a dd. Getting gears soon but it can be done. I get 12-13 around town an 16-17 on the hwy. Let me define hwy though. That's 65 mph tops. Reason being is the torque converter will constantly slip over 65 mph an makes the tranny get supper hot an push fluid out the vent. I have a tranny cooler sitting in the closet just haven't had enough time off work to get it in. It will help out a bunch but so will 4.88s. Bottom line anything is possible an even bearable for a certain length of time but ultimately doing it right is best. Rock the 35s but have plans to save up for some gears or atleast find a set of 4cyl axles with 4.10s to swap in for a temporary solution.

Cherokee9t8

For the last couple months (3000km), I've been running my 98 Cherokee with 34x12.5, automatic trans, and 3.55 gears. She's my daily driver and I drive her in any terrain/condition (city, highway, country). It does get a very noticeable difference in MPG on the highway over city, and usually cruises at about 110-120km/h at between 2000-2200rpm..

I'd love to gear change, but need to wait till I find a replacement for the Dana35..

Demolition_x

I have 33's and 3.07s and its manageable on the road its pretty decent. I feel like my clutch gets a workout getting it going from a stop but that might just be me.

When wheeling I seem to find my self always going in and out of 4 lo. you will be fine with the 3.55's with 33's

But that being said I have 4.88's waiting to be installed. I want to eliminate as much 4lo use as I can and save it for crawling.